66 



ART. 3. — B. KOTO 



Holes in 

 Ground 



Numerous holes (PI. Y. Fig. 2), evidently caused by 

 trajection of large disrupted blocks, were to be seen 

 on the western shore, varying in size from 0.5 to 6 m. in dia- 

 meter and 0.3 to 2 m. in depth. Shattered blocks with cordierite- 

 bearing white inclusions are still to be seen in the bottom of pits 

 made by them, or scattered about in the neighborhood by their 

 rebound. Electric discharges seem to have had nothing to do 

 with the making of the hollows. On the other hand, it seems 

 not improbable that a thick pumice -ash deposit on the ivet valley 

 bottom might have been puffed np by steam, generated hij the 

 advancinr/ and overriding fluent lava, and in this way some conical 

 pits may be formed in the ground. 

 The 12th, From uoou, tho earthquakes remarkably abated owing 



.\fteknoon ■"■ ./ o 



to the releasing of 



pent-up gases, 

 which opened a 

 way for the lava 

 to the surface ; 

 but ' air-quakes '^^ 

 or air -concussions 

 and roarings con- 

 tinued, increasing 

 both in frequency 

 and force, con- 

 stantly rattling the 

 windows even of 



1) The air-cxuake or (/«(«.si-earthquake is accompanied ■with the ' cletotiatioti ' — the air-wave, 

 which in contrast to the pure sound-wave is said to be i)roduced by slow oscillation of air. It 

 does not affect the human ear as a sound in itself, but it causes audible sounds when it encounters 

 some obstixcle which can be easily disturljed, such as Japanese sliding doors. See S. Fujiwara, 

 ' Abnormal Propagation of Süv;nd-waves in the Atmosphere.' Bull. Ceritr<d Meteor. Observntorij of 

 Japan Vol. H. No. 1, 1912. See also ' Morphological Summary of Japan and Korea.' III. Earth- 

 quakes. Joicr. <ieol. Hoc. Jajxtn, 1915, p. (26), footnote. 



Pig. 16. — Night view of Jan. 15, as seen fron 

 the quay in Kagoshima. 



